Results of transmyocardial laser revascularization in non-revascularizable coronary artery disease after 3 years follow-up [ssee comments].

BACKGROUND: Transmyocardial laser revascularization is a new therapeutic option for end-stage coronary artery disease if no other cardiological or cardiosurgical intervention is possible. Data are few on how patients fare after more than 1 year follow-up. METHODS AND RESULTS: From a total of 157 patients who were suggested for transmyocardial laser therapy in the years 1995-1997, 126 were judged to have non-revascularizable coronary artery disease (mean age 61.9 +/- 14 years, 80% men, mean left ventricular ejection fraction 46.2 +/- 17.1%). Sixty-six patients had a good clinical response to intensification of the antianginal therapy and were therefore treated further medically. In 60 patients with refractory angina, sole transmyocardial laser revascularization without cardiopulmonary bypass or additional grafts was performed. The transmyocardial laser revascularization group was 32% female; 78.3% patients had had bypass operations; the mean left ventricular ejection fraction was 53.6 +/- 15%. Eighty five percent of the transmyocardial laser revascularization patients had demonstrable ischaemic regions, as visualized by dipyridamol-MIBI scintigraphy. The percentage of patients with some hibernating myocardium in positron emission tomography studies was 70%. Good early relief of angina symptoms was experienced by patients who had undergone laser treatment. After 3 months the Canadian Cardiovascular Society class fell from 3.31 +/- 0.51 to 1.84 +/- 0.77 in 49 patients (P < 0.0001), but increased in the total group to 2.02 +/- 0.92 after 6 months (n = 47), to 2.26 +/- 0.99 after 1 year (n = 42), to 2.47 +/- 1.11 after 2 years (n = 38) and to 2.58 +/- 0.9 after 3 years (n = 19). MIBI/positron emission tomography data at rest and after 6 months was worse in patients in whom pre- and postoperative studies were complete (n = 22). The peri-operative mortality was 12% (n = 7: peri-operative myocardial infarction, low output syndrome, arrhythmia). Mortality after 1 and 3 years was 23% and 30%, respectively. The risk of transmyocardial laser revascularization was significantly elevated in patients with left ventricular ejection fraction < 40%. Late deaths (n = 9) were due to sudden arrhythmias or pump failure. There was a high rate of cardiac events and reinterventions in the transmyocardial laser revascularization group, including percutaneous transluminal coronary angioplasty in newly developed lesions (n = 7), valve replacement (n = 2), need for intermittent urokinase therapy (n = 5) and heart transplantation (n = 2). CONCLUSION: Fifty percent of patients with non-revascularizable coronary artery disease submitted for transmyocardial laser revascularization can be stabilized medically. Transmyocardial laser revascularization led to a rapid early relief of symptoms, but with a trend towards worsening over time and showed a high peri-operative risk (> 10%) dependent on the pre-operative ejection fraction. Our data were in contrast to other published reports on the more beneficial effects of transmyocardial laser revascularization and should lead to further investigation of this experimental method. Transmyocardial laser revascularization should only be performed after failure of maximal anti-anginal therapy, and should be avoided when the left ventricular ejection fraction is < 40%.

Transmyocardial laser revascularization induces cerebral microembolization.

BACKGROUND: Transmyocardial laser revascularization may vaporize fluid in the left heart, allowing bubbles to form. This study aimed to determine whether the laser pulse resulted in cerebral emboli and to examine changes in middle cerebral artery flow velocity and jugular bulb oxygen saturation (SjO2) during transmyocardial laser revascularization. METHODS: Twelve patients (American Society of Anesthesiologists physical status III) were studied after the authors received institutional review board approval and the patients' informed consent. Monitored variables included mean arterial blood pressure (measured in millimeters of mercury), heart rate (measured as beats/min), and partial pressure of carbon dioxide (measured in millimeters of mercury). A 5-MHz transesophageal-sonography system was used to record intraventricular events after laser injection. Mean blood flow velocity (Vmean; measured in centimeters per second) was monitored in the middle cerebral artery using transcranial Doppler sonography, and SjO2 (expressed as a percentage) was measured using a fiberoptic thermodilution catheter placed in the right jugular bulb. Data were recorded before, during, and for 4 min after laser injection. RESULTS: After laser injection, intraventricular echogenic contrast was seen in transesophageal-sonography, and 2-4 s later high-intensity signals (microemboli) appeared in the transcranial Doppler sonography spectra. As long as mean arterial pressure remained stable during the observation period, Vmean and SjO2 did not change. CONCLUSIONS: These data show that microemboli can be detected after laser injection in the middle cerebral artery, although they do not effect Vmean and SjO2. The results suggest that these microemboli do not induce a global oxygen imbalance.

Clinical data and histological features of transmyocardial revascularization with CO2-laser.

OBJECTIVE: TMR is a modern therapeutic approach in the treatment of patients with severe chronic ischemic cardiac disease. Clinical data from world-wide over 1800 TMR-treated patients shows that TMR can improve cardiac status in cases without preoperative congestive heart failure. The mechanisms underlying beneficial TMR-effects are not well understood. METHODS: The 61 patients of the Hamburg University TMR-trial were treated with a CO2-laser. Clinically, both a 6 and a 12 months follow-up were performed. Pathologically, hearts from four patients who died 3 (2 persons), 16 and 150 days after TMR, respectively, were examined by trichrom-and immunostaining (anti-collagen types I and III). RESULTS: In a 6 months follow-up clinical data indicates that TMR was able to improve clinical status in 50 of 61 laser-treated patients (82%), whereas 5 (8.2%) did not show any benefit evaluated by CCS grading and six (9.8%) died. CCS grade reduction was found in 22 patients with a 12 months follow-up (28 patients still in evaluation). Days 30, mortality amounted to 6.5%; late mortality (over 30 days) was 3.3%. Histopathological investigations revealed tissue remodeling comparable with different stages of wound healing. The cicatricial tissue in the original laser-created channels displayed a stronger immunostaining for collagen type III than for type I. CONCLUSIONS: Clinically, TMR improves cardiac function in some patients with severe ischemic cardiac disease, but pathophysiological data as well as morphological features from human myocardium could not explain this phenomenon. Therefore, TMR treatment should be used only as 'the last chance' in patients with severe angina pectoris.

Smoking after heart transplantation: an underestimated hazard?

OBJECTIVE: Risk factors for the development of vasculopathy and malignancies as the most important causes of morbidity and mortality after heart transplantation are not well defined. METHODS: Univariate and multivariate Cox regression analysis of the data derived from our 84 survivors of more than 3 months after orthotopic heart transplantation between 1984 and 1996. Measurement of carbonmonoxide-hemoglobin blood levels with an ABL 520 analyzer. RESULTS: Recipient or donor age, the mode of immunosuppression, total-, LDL- and HDL-cholesterol, the HDL/LDL-ratio, triglycerides, hypertension, diabetes mellitus, CMV status and rejection episodes had no independent influence on total mortality or the occurrence of graft vasculopathy or cancer. By means of an intensive questionnaire (in case of deceased patients, by their relatives) and measurement of CO-Hb blood levels we detected a high rate of patients who smoked after transplantation (22/84 = 26%). Four patients confessed smoking after undergoing the blood test. Non-smokers were defined as denying it in the questionnaire and having CO-Mb levels < 2.5% in repeated measurements. All but one were smokers before heart transplantation. Mean consumption was 11 cigarettes per day. Five and 10 years survival was significantly reduced in smokers vs. non-smokers (37 vs. 80% and 10 vs. 74%, respectively, P < 0.0001). Survival curves diverged dramatically after 4 years of observation. Smokers had a higher prevalence of transplant vasculopathy as revealed by coronary angiography and/or autopsy (10/22 smokers vs. 2/62 non-smokers, P < 0.00001) and a higher rate of malignancies (7/22 smokers developed cancer, as compared to 4 cancers in 62 non-smokers, P = 0.0001). The primary site of cancer was the lung in 5/6 smoking and lymphoma in all non-smoking cancer patients. CONCLUSIONS: Our data show that the prevalence of smoking after heart transplantation may be relatively high, especially in former smokers. Repeated measurements of CO-Hb could be helpful in its detection. Despite a relatively low cigarette count, smoking is a major risk factor of morbidity and mortality after heart transplantation (HTx). Approximately 4 years of exposure time is needed to uncover its negative influence. These findings should lead to aggressive smoking screening and weaning programs in every HTx center.

[Transmyocardial laser revascularization--a treatment option for coronary heart disease?]. / Transmyokardiale Laserrevaskularisation--Behandlungsoption der koronaren Herzerkrankung?

Transmyocardial laser revascularization (TMR) is a new therapeutic principle for patients with coronary artery disease and no possibility of conventional revascularization with CABG or PTCA. The clinical value of the method is not known. Therefore we investigated all 46 patients treated with sole TMR in our center using clinical investigation, LV and coronary angiography, right heart catheterization, MIBI perfusion imaging and myocardial FDG-PET pre- and 6 months post TMR. 117 patients judged not suitable for conventional revascularization procedures were submitted for TMR. The indication for the procedure was reevaluated in every case. 52 patients (mean EF 41 +/- 16%) could be further treated by intensified anti-anginal medication, seven patients received bypass grafts, four patients had PTCA, three patients were listed for heart transplantation, and five patients had a combined CABG plus TMR. Only 46 (38% of the submitted patients, mean EF 55 +/- 15%) were accepted for sole TMR. CCS class of these patients was 3.3 +/- 0.4, mean age was 63.6 +/- 7.3 years, 70% were males. The postoperative mortality within 30 days was 5/46 (10.8%); 9/46 patients (19.5%) suffered from perioperative myocardial infarction. Other complications were ventricular fibrillation in two cases on the second postoperative day and a rupture of the spleen on the 14th postoperative day. 8/46 patients (17%) had wound infections. Survivors showed an improvement in their CCS class (1.9, 2.1, 1.9 after 3, 6 and 12 months, respectively, mean observation time 0.61 +/- 0.4 years). These patients were able to perform bicycle stress tests significantly longer (98 s +/- 9 pre versus 120 +/- 13 s post TMR, p = 0.01). Angiographic EF fell from 57.8% +/- 15% to 52.6% +/- 19% (p = 0.02) and the number of hypokinetic chords rose from 23.6 +/- 20.9% to 30.6 +/- 24.1% per patient (p = 0.008), predominantly in the inferior wall. Nuclear studies showed reduced myocardial perfusion and vitality after TMR. Four patients in the TMR group had reintervention (PTCA) because of progression of coronary sclerosis of native vessels. One patient had mitral valve replacement due to severe regurgitation. Kaplan-Meier analysis showed no significant difference in survival between the TMR and the medical group when stratified according to initial ejection fraction. Sudden death and congestive heart failure are the most important causes of mortality. Our data show that TMR improves symptoms and exercise performance of otherwise not treatable patients with diffuse coronary artery disease. Due to a lack of an improvement of cardiac perfusion, function or prognosis TMR should be used only in highly selected cases when conventional methods fail to improve patients symptoms.

Transmyocardial laser revascularization. Histological features in human nonresponder myocardium.

BACKGROUND: The creation of transmyocardial channels from the epicardium to the left ventricular cavity with the use of a CO2 laser is a modern approach in the treatment of patients with chronic ischemic cardiac disease. The histological features of human myocardium at different times after transmyocardial laser therapy have not been previously described. We had the opportunity to examine hearts from patients who died without clinical evidence of a persistent therapeutic effect at 3, 16, and 150 days after transmyocardial laser revascularization (TMR) respectively. METHODS AND RESULTS: We grossly localized the laser-created channels in unfixed and formalin-fixed tissue. Three ventricular levels were defined for cutting the hearts into four segments. Then, transmural blocks were excised and cut crosswise and lengthwise for histological investigation through the use of established staining methods. On day 3, laser-induced channels were filled with abundant granulocytes and thrombocytes, fibrinous network, and detritus and were surrounded by severe myocardial necrosis. Furthermore, the epicardial and endocardial portions were obstructed by fibrinous network and microclots. Granulocytes were mostly absent on day 16; in addition, the channels were filled with erythrocytes or fibrinous network. On day 150, we observed a string of cicatricial tissue admixed with a polymorphous blood-filled capillary network and small veins, which very rarely had a continuous wrinkled link to the left ventricular cavity. CONCLUSIONS: We found different stages of wound healing in human nonresponder myocardium after TMR, resulting in scarred tissue that displayed capillary network and dilated venules without evidence of patent and endothelialized laser-created channels. Experimental studies are necessary to analyze the morphological basis for TMR-mediated effects in human responder myocardium.

[Delayed surgical therapy of acute aortic rupture]. / Verzögerte chirurgische Therapie der akuten Aortenrupturen.

Immediate surgical treatment of traumatic aneurysms of the aorta is in our point of view in most cases problematic, also because of the combination with life threatening injuries of other organ systems. In our own patient-collection seven patients out of 44 with traumatic transsection were immediately operated. Six patients died in tabula, three of them due to uncontrollable hemorrhage. An analysis of over 5,000 post mortem findings from the department of forensic medicine in Hamburg revealed that injuries of the aorta lead in 98.3% to death in the first two hours after the accident. This shows that only a small number of injured victims survive. The danger of a two stage rupture is judged differently. We did not observe this problem in the patients with aortic lesion following blunt chest trauma and stable conditions who had first undergone treatment for other injuries and therefore operated in the interval period after two to ten weeks. With this strategy the lethality involving surgical management of aortic injuries in our unit decreased to 13%.